Electrical switch



June 20,- 1933. E. R. EVANS ELECTRICAL SWITCH Filed May 1, 1930 I m I IPatented June. 20, 1933 Pars EARL B. EVANS, OF WASHINGTON, DISTRICT OFCOLUMBIA ELECTRICAL SWITCH Application filed May 1, 1930. Serial No.448,960.

My invention relates to electrical switches and more particularly tomanually-operated enclosed switches.

One obj ect of my invention is to provide a switch adapted for use as awall swltch but having no projecting levers or actuating buttons as inthe ordinary wall switch.

Another object of my invention is to provide a switch having a flexibleor deformable cover plate operatively connected to contact orcircuit-closing mechanism of the mercury 3r liquid-flow type.

A further object of my invention is to provide a wall switch of improvedconstructlon embodying a tight, dust-proof casing of attractiveappearance.

A. still further object of my invention is to provide an improved switchof the liquidcontact type.

A switch embodying the invention is illustrated by way of example in-theaccompanying drawing, in which Fig. 1 is a front view of a switch of thewall type;

Fig. 2 is a sectional view on the line 22 of Fig. 3; and i Fig. 3 is afront View of the switch with the cover plate removed.

The wall switch shown in the drawing comprises a box 1, of porcelain orthe like, which is closed by a cover plate 2 of metal, bakelite or othersuitable material. The cover plate 2 is preferably imperforate orsubstantially imperforate and forms with the box 1 a tight, dust-proofcontainer for the switch mechanism. The cover plate 2 is also flexibleor deformable and is arranged to cooperate with the switch mechanism tooperate the same upon fleXure of the cover plate, as indicated in dottedlines in Fig. 2. An integral button portion 3 may be formed in the coverplate 2, as shown, to indicate the point at which pressure should beapplied to actuate the switch.

The boX 1 is provided with a liner 4 to which the cover plate 2 issecured by screws 5. Various other means may be employed for holding thecasing, switch mechanism and cover plate in assembled relation withoutdeparting from the scope of the invention.

The preferred switch mechanism embodies a mercury contactor 10 of theliquidflow type in order to provide noiseless operation and obtainmechanical simplicity; although any suitable or usual switch mechanismmay be employed. The mercury contactor 10 is of the usual constructionand embodies a tube of vitreous material con taining contacts adapted tobe bridged by a body of mercury or other liquid conductor, the tubebeing pivoted upon the projecting lugs 11 and 12 of the lining 4. Thetube 10 is preferably encircled by a clamping band or ring 13 havingprojecting pivotal pins 14 engaging the lugs 11 and 12. The clampingband 13 is further provided with integral cam members 15 and 16 adaptedto cooperate with the actuating member 17, and is held in position bythe screw or bolt 18. The actuating member 17 is secured to the coverplate 3 and is adapted to engage the cam members 15 and 16 to open andclose the circuit including conductors 2O alternately upon successivedepressions of the cover plate, the weight of the mercury in the tube 10tending to hold the contactor in its actuated position in each instance.

The cover plate 2 may be either fiat or of any desired configuration andsize, provided a portion thereof may be flexed or deformed to actuatethe switch mechanism. Since no projecting buttons. or toggle levers areemployed, the switch is attractive in appear ance and may be colored orornamented to conform to the wall decoration where it is used. The useof liquid-contact switch mechanism is preferred because of the smallenergy required to operate such mechanism and because of its noiselessoperation. Various modifications in the structure of the respectiveelements of the switch described and shown herein and in the connectionbetween the cover plate and contactor particularly, may be made withoutdeparting from the scope of the invention as defined in the appendedclaims.

What I claim is:

1. An enclosed electrical switch embodying a box-like enclosure ofinsulating material, a flexible substantially imperforate plate memberin front of the enclosure for said switch,'a switch element of theliquidflow type pivoted adjacent said plate member and means foroperating said switch element in response to the flexure of said plate.

2. An electrical switch embodying a hollow enclosure, a thin imperforatecover plate therefor, a tiltable mercury switch element and meanscooperating with said cover plate and switch element to open and closethe circuit alternately upon successive depressions of the cover plate.

3. An electrical switch embodying a casing and a tiltable mercurycontact device in said casing, the casing including a yielding platemember provided with cam operating means for tilting the contact device.

4. An enclosed switch having a casing provided with a deformable wall, atiltable mercury contactor in said casing and means for tilting saidcontactor to operate the same upon deformation of said wall.

5. A wall switch comprising a casing adapted to be mounted in a wall, animperforate front cover-plate secured thereto, said cover-plate being sothin that it is read: ily deformable by the pressure of the fingers, amovable switch element of the liquid-flow type mounted in said casingand means cooperating with said switch element for actuating the sameupon a movement of aportion of the cover-plate.

6. A wall switch comprising a casing adapted to be mounted in a wall, afront cover-plate of thin, flexible insulating material secured theretoand switching means of the liquid-flow type in said casing operativelyassociated with said cover-plate.

7. A wall switch comprising a hollow insulating enclosure adapted to bemounted in a wall, a front cover-plate therefor of thin, flexiblematerial, a switch-operating member projecting from the back of saidcoverplate and operated by flexure of said coverplate, and switchingmeans of the liquidflow type in said enclosure in the path of movementof said switch-operating member to be actuated thereby.

In testimony whereof I aflix my signature.

EARL R. EVANS.

